BARCELONA, SPAIN — BADALONA, Spain -- Oscar de la Hoya, in the most impressive performance of his amateur career, knocked a strong, brave, but overmatched Brazilian all over the ring last night in the lightweight's Olympic debut.

De la Hoya, criticized by some at the Olympic trials in June for a slow-paced, conservative style, came out aggressively against Adilson Silva.

It was by a wide margin the most impressive performance yet in the Olympics by American boxers, who are 8-2. After de la Hoya won, light-welterweight Vernon Forrest lost a decision to Britain's Peter Richardson.

De la Hoya snapped Silva's head back repeatedly with powerful, stinging left jabs, folded him in half with wicked left hooks to the ribs and stunned him often with uppercuts to the chin. He was fast and up-tempo, and he fought his opponent with a confident, driving rhythm that Silva could never interrupt.

De la Hoya's rousing victory occurred before the largest crowd yet at the Olympic boxing venue, Joventut Pavilion -- about 2,000. And 10 of them were family members and friends of de la Hoya's, who occupied a balcony section behind their long, white banner:

"Good Luck Oscar -- We Love You!"

De la Hoya, who has dedicated a hoped-for gold medal to his mother,who died in 1990, put himself in the second round of the preliminaries. He boxes Moses Odion of Nigeria tomorrow. Shortly after de la Hoya's bout, Cuban Julio Gonzalez was upset on an 11-10 decision by Bulgarian Dimitrov Tontchev. Tontchev, then, looms as a possible semifinal foe for de la Hoya.

In the top half of the 132-pound bracket, the boxer who beat de laHoya at the world championships in Sydney last November, German Marco Rudolph, looked like a medal-round athlete in defeating Romanian Vasile Nistor, 10-5.

Last night was the end of a long wait for the de la Hoya clan . . . and despite their athlete's one-sided victory, they had some anxious moments. Early in the second round, de la Hoya was cut beneath his left eye by a Silva right hand. The cut bled freely the rest of the way, and was inspected by a doctor in the third round.

Later, the boxer said it amounted to more blood than cut.

"It's just three little scrapes, it's nothing," he said in the interview room, holding a bag of ice to the cut. Team physician Dr. John Lehtinen said the cut was more of a small abrasion, that it was no threat to keep him out of the tournament.

De la Hoya stung the Brazilian with the first punch of the bout, a stiff left jab. Dozens more followed. De la Hoya put Silva on his back with a left hook that he said caught the Brazilian on the chin.

After the standing-eight count, de la Hoya rushed his foe with a flurry of body shots, but got caught himself on the chin by a desperation right hand by Silva. The punch briefly wobbled de la Hoya, and caused him to back up a step.

By the end of the first round, de la Hoya had given Silva a bloody nose. He was double- and triple-jabbing him. He snapped his head back with a left hook with 12 seconds to go. Silva fought back, but with considerably less firepower than his opponent.

The cut under de la Hoya's eye appeared 10 seconds into the second round, but it never seemed to faze him.

By the end of the second, de la Hoya's rapid-fire, powerful jabs were backing Silva up by a step each time. De la Hoya, who had a 9-2 computer score lead after one round, was up by 15-3 after two.

At the finish, de la Hoya had a 24-9 lead.

Redo stopped the bout with seven seconds left when de la Hoya was hitting Silva at will with uppercuts.